Some X-ray inspection systems have a plurality of fixed irradiation planes for nondestructive inspection of objects (inspection objects). An inspection of this kind can be carried out, for example, in the context of security screening of luggage at airports. During the inspection, an inspection object is conveyed through the plurality of irradiation planes that are each output by a respective stationary radiation source. The intensities of X-rays that are not absorbed by the inspection object and its contents are measured by detector arrays associated with the radiation sources. The intensity values measured are evaluated and used, among other things, for producing X-ray images of the inspection object, based on which a screening of the contents of the inspection object can be carried out.
Particularly with regard to an automated screening, containers such as bottles that are carried in luggage are problematic. Bottles can contain dangerous liquids. This is why liquids can only be brought aboard aircraft in small quantities, if at all. In the prior art, when performing security screening of hand luggage at airports, security personnel must first recognize such containers in X-ray images and then have to remove them from the luggage for a visual inspection. This additional inspection effort causes delays in passenger handling. This is similarly problematic with checked-in luggage. There, too, a piece of luggage must, for example, be removed from automatic handling and brought to a manual inspection station where it may be necessary to open the piece of luggage for a visual inspection and if need, additional inspections may be necessary. This also causes delays.
Some methods for identifying items (blobs) contained in an inspection object and to be found in an X-ray image of the object. For more precise identification, the detected blobs are inspected, among other things, for symmetry. Similarly to this, a bottle may be placed in a special box before X-raying so that the bottle is oriented at a known angle relative to the surface on which it is standing so that for an evaluation of the X-ray image of the bottle with regard to a possible threat potential of its contents, all geometric information with regard to the position of the bottle are known.